<html>
<head>
<style type="text/css">
p:first-child em { color: red }
</style>
</head>
<body>
<h1>H1</h1>
<div>
    <p>fzz <em>em</em></p>
    <p>fzz <em>em</em></p>
</div>
<h1>H1</h1>
<p>todo as usual works in chrome, not in IE or Word.</p>
</body>
</html>